This build uses crit with multiple sources of added damage from physical, 100% elemental conversion, and several cast speed boosts to achieve over 700,000 PoB DPS fully buffed. Since Glacial Cascade hits twice per cast over most of its range, this translates to over 1.4 million top-end DPS in practice.

Mitigation is provided through 64/64 unbuffed dodge supplemented by a Quartz Flask and Vaal Grace as well as modest evasion and block. Vaal Pact with Warlord's Mark, Doryani's Catalyst, the leech boot enchantment, and a CWDT leech setup provide sustain.

The build is capable of killing all guardians, Shaper, and Uber Atziri while maintaining respectable clear speeds.

This is a mostly optimized damage setup. Controlled Destruction actually gives better numbers than ICS, but especially with Vaal Pact I find that consistency is important. You could swap Conc Effect for Increased AoE for clearing if you want, but a few AoE nodes on the tree will mostly offset its drawback.

Shield Charge should go in Doryani's to take advantage of Elemental Proliferation; you will usually chill, and sometimes freeze, packs this way. Vaal Grace is basically there as a backup in case you run out of Quartz Flask charges.

1-Link:Summon Ice Golem

Mostly this is a carrier for Onslaught, but it's also nice to be able to re-summon it on demand in some fights.

Equipment

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Gearing Strategy

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First and foremost, you want to get a helmet with the "40% of Glacial Cascade Physical Damage converted to Cold Damage" enchantment. Getting that full elemental conversion is a huge DPS boost, and the only other options for it are Phys to Lightning, Hrimsorrow, or a passive node cluster that's five points out of your way.

Otherwise most of the equipment in this build is focused around stacking dodge, since that's our main source of mitigation. It might be hard to find a good evasion/ES shield with both dodge rolls and DPS mods; you'll probably have to prioritize one or the other for a while and just keep an eye on poe.trade.

Spell damage, physical damage, elemental damage, cold damage, and AoE damage will all scale 100% of your output. Crit chance and multi are great where you can get them. Finally, you need life and resistances wherever you can squeeze them in.

Current Gear

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Explanation of Unique Items

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There are better rare weapons in terms of raw DPS, but Doryani's is the only source of always-on leech for this build that covers both cold and fire damage. If you socket your Shield Charge setup in it, you can also chill or freeze packs when you charge into them because of the free Elemental Proliferation.

Self-cast builds are very mana hungry; the Covenant lets you not worry about that. Instead of investing in regen nodes and mana leech, you can ignore them completely and reserve almost all of it with Hatred and heralds.

Intimidate is great, crit mitigation is great, nobody ever complained about increased physical damage, and the resists and life are icing.

Onslaught gives you a significant boost to both clear speed and movement, and having it available on demand is really strong. Since we're stacking dodge, the extra 5% here is also notable.

More dodge. These could easily be swapped out for some rare boots and a nasty DPS amulet or Bisco's, but the extra mitigation really makes a difference in higher tier content.

This is a luxury item and the thing I would recommend getting last if you're on a budget. If you feel like your survivability is alright, you can run Blood Rage for frenzy charges instead.

Alternatives

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Lab runners love Rat's Nest and Starkonja's Head, and you can probably find one of those with the 40% GC conversion enchantment much cheaper than a rare helmet. I would personally recommend Starkonja's for the flat life.

If you can't afford the enchant, Hrimsorrow is your next best alternative.

Before you path over to Vaal Pact and Acrobatics, Mind over Matter will be your best defensive option; running Hatred on Essence Worm is great for this and will allow you to take full advantage of your extra blue life pool.

Carcass Jack and Skin of the Loyal are both fine body armors, though I would shy away from Skin unless you're already over 5k life. Note that if you run either of these you should consider carrying a mana flask for boss fights, drop Herald of Ice, and honestly consider dropping Herald of Ash too.

Maligaro's Virtuosity is, as ever, a great DPS unique for crit builds if you can afford not having life or resistances on your gloves.

If you don't need the DPS from intimidate and have your life pool handled from other gear, the extra leech from a fire Doryani's Invitation can be nice. We're not berserkers, so it's good to pick it up where we can.

Berek's Grip is another good source of sustain with some okay DPS mods on top. The leech is conditional, but that condition is easy to fulfill as long as you're judicious about keeping Orb of Storms up.

Eye of Innocence with Mokou's Embrace is yet another great leech source packaged with a hefty damage boost. It's a shame you have to choose between this and Hinekora's. If you run this combo, drop Elemental Focus for Hypothermia.

Inevitable Judgement is why we're playing Inquisitor, so the first four points go to that. Instruments of Virtue is another big DPS boost, and the extra attack and cast speed greatly improve clearing. Augury of Penitence is solid mitigation and yet another strong damage boost.

Just to note, Labyrinth can be kind of hard on Vaal Pact characters. Take a couple of life flasks and Soul of Ryslatha for Merciless and Eternal, and don't rush it.

General
Honestly, just pick an elemental spell to start out with. I used Spark. You can switch to GC from level 28, but if it feels too slow without cast speed gear feel free to keep using your starter skill for a while.

Mind over Matter is super close to the Templar starting point; definitely take advantage of this. Just be aware that once you path over to VP and get a decent life pool going, you'll eventually turn a corner where running out of mana from MoM kills you more often than straight up damage. When that happens, it's time to put those four points elsewhere.

Build Variant - EK Part Timer

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Well we're in a clear speed meta, so it's always worth giving some thought to optimizing that even on boss-capable DPS builds. As it happens this build has a lot in common with EK nova in terms of tree and gearing, and you can easily clear 300k DPS with Ethereal Knives - Spell Echo - Hypothermia - Physical to Lightning in a Tempest's Binding or Essence of Insanity helmet. Better still, this will allow you to run elemental reflect maps as long as you don't try to take on the boss.

Your opportunity cost here is a jewel slot for Ring of Blades, a little bit of safety from the level 20 CwDT links, and the cost of finding or crafting an appropriate GC-enchanted helmet.

Level 3 Enlighten reduces mana cost and reservation for linked skills by 8%, leaving you with ~80-100 max mana for everything except GC. Because you're still regenerating relative to the full pool, it fills back up faster than you can use it.

Found this build to be really bad don't understand why you use vaal pact when your not build into life leach apart from eternal knives skill and that's very inconsistent and you have a accuracy amulet on and GC doesn't use accuracy?

Found this build to be really bad don't understand why you use vaal pact when your not build into life leach apart from eternal knives skill and that's very inconsistent and you have a accuracy amulet on and GC doesn't use accuracy?

I think the author of this build focuses on dodges. This is why he uses the accuracy amulet. Yes, that 1000 accuracy is totally wasted for GC. This build looks new to me as an Inquisitor. For leeching, I think he takes advantages of Atziri's Promise and Doryani's Catalyst. But I don't know this is enough leech for inquisitors because we are squishy and require more leech to survive.

I am following this 100% fire conversion build https://www.pathofexile.com/forum/view-thread/1966270.Without life leech gem or Berek's grip ring, I barely survive to Harbinger or fast-moving mobs. Maybe the dodge % can help mitigate this (I tried taking Acrobatics Node and still haven't seen any difference yet).

The reason i went for 100% fire conversion is I don't need the helmet enchantment and only need the cold to fire gem and AVATAR of FIRE(which is an easy-to-grab node for Templar). I find any build that requires helmet enchantment expensive and inconvenient.

One thing I am interested in is the unique chest which has blood magic and this allows you to reserve 100% mana for auras. Also the use of EK for clearing looks very neat. An extra gem slot wouldn't cost much for higher levels.

Before the ES nerf, Templar wouldn't have to travel to the Shadow's area to grab life nodes... and now need to grab dodge nodes. I find it very hard to play Templar compared to Witch because they have ascendancy points for more ES.

Merlins - You get leech from Doryani's, Warlord's Mark, the boot enchant, and Atziri's Promise when it's up. Lately I've been messing around with Eye of Innocence/Mokou's, but the extra leech doesn't seem to be worth the opportunity cost which I allude to in the OP.

The build runs Hinekora's Sight purely for the dodge; we don't care about accuracy or blindness. The survivability you gain from that last 10% is similar proportionally to what you gain from taking the Acrobatics chain in the first place. 74% damage mitigation straight off the top is worth a few dead mods.

thin - the GC enchantment has definitely exploded in price since the start of the league because of all the sabo miners. Hrimsorrow is probably the cheapest and easiest way to get around it, and it's worth considering anyway to get the full conversion on EK.

I really like the concept of the build you linked, but it doesn't have much mitigation and the DPS is low, which means the leech is also going to be low. You could probably do some optimization and get it to a good place though.

Not gonna lie I forgot all about Berek's Grip, and that's a really good ring for this build. I was using one earlier in the league but dropped it once I started running the Covenant and dodge gear. I'll add it to the guide.

I just realized Avatar OF Fire doesn't allow me to deal other types of damage. I found this very inconvenient dealing with fast-moving mobs.so I switched to your build and it worked out very well.

I got the unique gloves for 1c and got all physical dmg converted to cold. I'll prolly look for an enchanted helmet if i have enough currency.

For gears, I only have a shield that provides dodge %. My current dodge to attack is 42% and spell dodge is 32%. I was able to kill Hydra and Minotaur easily. So far, I don't have any issue with leeching.

Also played with pandemonius amulet but this only chills the mob and bosses. Do you think using The Halcyon Amulet with Glacial Cascade will be able to freeze bosses like Freezing Pulse does?